title: Simplified preformed chelate protein radiolabeling with technetium-99m mercaptoacetamidoadipoylglycylglycine (N3S-adipate).
abstract: A simplified kiet has been developed for 99mTc protein radiolabeling using an N3S triamide mercaptide bifunctional chelating agent and the preformed chelate approach. The process combined N3S chelating agent, gluconate intermediate transfer agent, stannous reducing agent, and gentisic acid stabilizer into a lyophilized formulation. With sulfur donor atom hemithioacetal protection of the ligand, delta-2,3,5,6-tetrafluorothiophenyl alpha-S-(1-ethoxyethyl)mercaptoacetamido-L-adipoylglycylglycine , optimum 99mTc chelation was achieved in a single step. Subsequent reaction with NR-LU-10 antibody Fab fragment followed by purification via QAE Sephadex anion exchange resin filter afforded 99mTc-N3S-NR-LU-10 Fab conjugate with retained immunoreactivity and effective tumor targeting properties.
authors.affiliation: NeoRx Corporation, Seattle, Washington 98119, USA. skasina@neorx.com
authors.forename: S
authors.initials: S
authors.lastname: Kasina
authors.forename: J A
authors.initials: JA
authors.lastname: Sanderson
authors.forename: J N
authors.initials: JN
authors.lastname: Fitzner
authors.forename: A
authors.initials: A
authors.lastname: Srinivasan
authors.forename: T N
authors.initials: TN
authors.lastname: Rao
authors.forename: L J
authors.initials: LJ
authors.lastname: Hobson
authors.forename: J M
authors.initials: JM
authors.lastname: Reno
authors.forename: D B
authors.initials: DB
authors.lastname: Axworthy
authors.forename: P L
authors.initials: PL
authors.lastname: Beaumier
authors.forename: A R
authors.initials: AR
authors.lastname: Fritzberg
mesh_terms: D000818:Animals; D002614:Chelating Agents / Q000737:chemistry* / Q000493:pharmacokinetics; D003110:Colonic Neoplasms / Q000378:metabolism; D005841:Gentisates; D005942:Gluconates; D062385:Hydroxybenzoates; D007140:Immunoglobulin Fab Fragments; D000922:Immunotoxins / Q000737:chemistry; D007202:Indicators and Reagents; D007553:Isotope Labeling / Q000379:methods*; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics; D014018:Tissue Distribution
chemical_list: D002614:Chelating Agents; D005841:Gentisates; D005942:Gluconates; D062385:Hydroxybenzoates; D007140:Immunoglobulin Fab Fragments; D000922:Immunotoxins; D007202:Indicators and Reagents; D015609:Organotechnetium Compounds; C030691:gluconic acid; C010925:2,5-dihydroxybenzoic acid